This invention relates to the field of polymer films and methods for forming such films, and in particular, to a film possessing a polyolefin core layer faced on at least one side thereof with a skin layer containing a silicone grafted polymer.
Heat sealable multilayer films which are useful as packaging materials are known in the art.
U.S. Pat. No. 6,165,444 describes a cosmetic or dermatological composition for treating keratinous material, particularly human hair, including a cosmetically or dermatologically acceptable medium containing at least one silicone-grafted polymer with a polysiloxane portion and a portion consisting of a non-silicone organic chain, wherein one of the two portions constitutes the main polymeric chain while the other is grafted onto said main chain, an at least one selected fatty-chain amide. Such compositions are particularly suitable for use as rinsable or non-rinsable products for washing and conditioning hair, hair setting or hair styling. U.S. Pat. No. 6,165,444 is incorporated herein by reference in its entirety.
U.S. Pat. No. 6,106,820 describes a cosmetic compositions comprising: (a) from about 0.1% to about 50%, based on the weight of the composition, of a film-forming graft copolymer, wherein the copolymer comprises: (i) a backbone exhibiting a T[g]of from about 0xc2x0 C. to about 50xc2x0 C.; and (ii) one or more hydrophilic grafts attached to the backbone wherein each of the grafts exhibits a T[g]of from about 50xc2x0 C. to about 200xc2x0 C., and wherein the average molecular weight of each of the grafts is greater than about 1000; and (b) from about 50% to about 99.9%, based on the weight of the composition, of a suitable carrier. The compositions provide good wear properties and are suitable for use in a variety of cosmetic applications, such as facial moisturizers, foundations, lipsticks, mascaras, nail polishes and the like. In a preferred embodiment, the compositions are in the form of a nail polish which, when applied to nails, exhibit excellent long wear properties. U.S. Pat. No. 6,106,820 is incorporated herein by reference in its entirety.
U.S. Pat. No. 6,104,422 describes a sublimation thermal image transfer recording method for thermally forming images on an image receiving sheet prepared by forming a dye-receiving layer on a substrate, includes the steps of superimposing a sublimation thermal image transfer recording sheet which has a substrate and at least one recording layer formed thereon containing a sublimable dye, on the image receiving sheet in such a manner that the recording layer of the recording sheet comes into contact with the dye-receiving layer of the image receiving sheet, recording images on the dye-receiving layer of the image receiving sheet by applying thermal energy Ei imagewise to the recording sheet from the substrate side thereof using a thermal head, and subjecting the image-bearing image receiving sheet to heat treatment by applying thermal energy Eb to the image receiving sheet using the thermal head through a sheet member for heat treatment, the thermal energy Eb being smaller than the thermal energy Ei. In the image receiving sheet, an overcoat layer may be formed on the dye-receiving layer, the overcoat layer having a dynamic friction coefficient of less than 0.45 which is measured in accordance with ASTM-0 1894 and containing a silicone resin and a lubricant. U.S. Pat. No. 6,104,422 is incorporated herein by reference in its entirety.
U.S. Pat. No. 5,854,356 describes a polymer for release films of surfaces containing pressure-sensitive adhesives. The polymer includes a reactive polyolefin and a reactive release substance, which are chemically bonded together as a result of being compounded in a molten state. The invention also relates to a release film for surfaces containing pressure-sensitive adhesives. U.S. Pat. No. 5,854,356 is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,237,334 describes a laminated insulating paper formed of cellulose paper or papers which is adhered to at least one side of cross-linked silicone grafted polyolefin film and to an oil-filled (OF) cable which insulated by the laminated insulating paper. The laminated insulating paper has outstanding peel strength as well as excellent non-solubility and anti-swelling properties in insulating oils. U.S. Pat. No. 4,237,334 is incorporated herein by reference in its entirety.
U.S. Pat. No. 4,734,317 describes a polyolefin film having a base layer composed essentially of propylene polymers and having sealing layers present on both sides, composed essentially of sealable olefin polymers. Polydialkylsiloxane is incorporated in a first of the two sealing layers, and this layer is not subjected to corona treatment. The second sealing layer is subjected to corona treatment and has polydialkylsiloxane, not incorporated, but present on its outer surface, the polydialkylsiloxane having been transferred to this layer by contact with the sealing layer in which polyidalkylsiloxane is incorporated. The relative polydialkylsiloxane occupancy on the second layer, which is determined by means of ESCA spectroscopy, is not more than 15. The three-layer polyolefin film is prepared by a coextrusion process. It is particularly suitable for use as a packaging film on high-speed packaging machines. U.S. Pat. No. 4,734,317 is incorporated herein by reference in its entirety.
U.S. Pat. No. 6,074,762 describes a block-resistant film which comprises a core layer of a thermoplastic polymer having a first side and a second side; a functional layer which is printable or sealable or treatable for printing or sealing is on the first side of the core layer, and a block-resistant layer is on the second side of the core layer. The block-resistant layer comprises a thermoplastic polymer and an amount of a polydialkylsiloxane, based upon the entire weight of the block-resistant layer, sufficient to inhibit blocking of the block-resistant layer to the functional layer when they are in contact and which polydialkylsiloxane deposits silicon onto the functional layer but the amount of silicon deposited is not substantially detrimental to the printing function or the sealing function. U.S. Pat. No. 6,074,762 is incorporated herein by reference in its entirety.
In accordance with the present invention, there is provided a polymer film possessing a low coefficient of friction, which comprises:
(a) a core layer comprising a polyolefin wherein the core layer comprises the interior of the film;
(b) a first skin layer comprising a silicone grafted polymer, wherein the first skin layer is exterior to the core layer.
The advantages of the present invention include one or more of the following:
A film which can be sealed on both sides.
A film which can be treated on both sides.
A film which is composed of multiple layers.
A film which has high scratch resistance.
A film which has good slip properties
A film which is transparent
A film which has good printability
A film which has decreased coefficient of friction
A film which has decreased hot slip
A film without loss of sealability after treatment
A film with less silicone fall out at the surface
A film with chemically bonded silicone
For a better understanding of the present invention, together with other and further objects, reference is made to the following description, taken together with the accompanying drawings, and its scope will be pointed out in the appended claims.